In pursuit of my low light photography passion I an considering purchasing a speed light. because I am so new to photography I am unsure of what the results will be using a speed light flash instead of the built in flash of the camera body.

I had been reading up on this and aside from the difference being like night and day I cant really find anywhere to quantify the results of using a dedicated flash instead of the camera's flash.

Can any one with a dedicated flash chime in and explain the difference in image results and any differences in the act of taking pictures with a speed light?

With built-in flash, all you can do is light it full on. This leads to bland pictures, without much interesting going on.

With the dedicated flash and no external hardware, you can actually point the flash in a different direction. A common thing to do is to point it straight up. This will "bounce" the flash on your subject, giving them a much more natural look. It will also tend to light up the whole scene much better, and almost never produces red-eye. It also avoids weird shadows, as the shadows tend to be in the downward direction.

These two shots, the fist one uses bounce flash, the second doesn't. Notice the second one has alot more reflections, is blown out in some areas, and generally has less detail. I think I used a diffuser for it, but it's still harsher then I would have liked, but sometimes you've just got a moment to get a shot, so...

Hah, beat me by a minute with basically the same answer. :)
–
mattdmJan 9 '11 at 0:36

LOL, it often happens with these basic questions;-) It looks like there was actually 3 answers that basically said the same thing within a few minutes of each other...
–
PearsonArtPhotoJan 9 '11 at 0:46

Can you also adjust the strength of the flash in order to get a hint of glow on the subject in a dark room?
–
kacalapyJan 9 '11 at 0:51

1

Another advantage of speedlights is the abiity to adjust power settings quickly without digging around in the menu like for your pop-up flash.
–
Evan KrallJan 9 '11 at 0:53

1

The boy seems to be lighted both by direct flash (key) and bounce light from ceiling (fill). Neither of them reaches under chin, which explains the hard shadow. Bounce alone would have left a longer and smoother shadow, catchlights would be missing and the hair on top of head would have been lighter. Diffuser would not have made the cheeks stand out so well and the shadow would have been smoother.
–
ImreMar 22 '11 at 0:15

Power: Even the most basic hotshoe flash will have 3-4x the raw power of the built-in flash. This allows light to cover more of the scene, making it all look better. A mid-range flash is 2-3x the power yet again, and so on.

Bounce: a decent hotshot flash (including Nikon's entry-level SB-400) can tilt, allowing you to bounce light from the ceiling, giving a wide, diffuse light source, with no ugly shadows. This is where the "night and day" comments come in.

And, beyond this, many mid-range and up flashes can be triggered (with full exposure control) via wireless optical remote. (Your D7000's built-in flash can act as the controller for this). That gives you even more control over how light falls on the scene, without the added bulk of a big shoe-mounted flash.

There was a answer that mentioned bounce cards, in response to that post that disappeared: Sound like the additional benefits of bBounce cards would be desirable in use with all flash applications. Why don't speed lights come with this feature built in? Would you not want to bounce light from above, below, and more locations to get light distributed evenly on the subject?
–
kacalapyJan 9 '11 at 0:58

Many flashes do have a built-in pull-out bounce card. They work, but are rather small (by nature). As for where you want light, that depends. There have been some great posts here recently on portrait lighting.....
–
mattdmJan 9 '11 at 2:53

The pull-out bounce cards are there to create catchlights in the subject's eyes, not for creating a competing direction for light.
–
ImreMar 22 '11 at 0:23

ability to pop the speedlight multiple times from different angles and locations during a shot with long shutter speed (at least several seconds), creating a photo that looks like one made with many light sources

some entry-level cameras use strobing light from pop-up flash as AF assist light; the AF assist beam built into some speedlights is much more discrete

There are also some negative aspects for speedlights:

more batteries and backup batteries are needed, perhaps even a separate charger

need to remember actually charging the flash batteries before going out to shoot

you'll have more stuff to lug around

if you envy point-and-shoots for their small size, your camera will be even bigger and heavier with a speedlight attached

some flashes, especially cheaper ones, may make an annoying high-frequency whistling sound while switched on; good luck finding that from tech specs

more possibilities implies that usage is more complicated than for pop-ups

+1 for marital problems and loathing photos. My wife actually says "can you just take a normal photo this time?" when I start to go for my stand & umbrella. My answer is usually "no". :-P
–
Craig WalkerMar 21 '11 at 21:46